Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field.
The management and treatment of domestic sewage and other waste is a growing problem facing cities and other populated areas. In highly populated areas, there is often a lack of appropriate sewage treatment facilities. If the sewage is not appropriately treated, it can contaminate water supplies and subsequently affect the health of inhabitants. There are an increasing number of areas where septic systems are causing problems with odour. Moreover, their impact on groundwater quality, and their use without some form of upgrade is being discouraged. In some areas, new septic systems are banned.
One approach to the problem has been the development of onsite treatment systems that either incorporate a septic system or use a similar anaerobic process as the first stage of the treatment system. They are often followed by a bioreactor/aeration system. Clarification follows either by settling, sand filtration, and in a few cases membrane filtration.
Many of these onsite treatment systems have relatively high operating costs, are often unreliable and require regular servicing. In the majority of systems there is a need to remove solids from the system and take away from the site on a regular basis (e.g. every 1-3 years depending on the load on the system). Government authorities are very concerned about the lack of management of these systems and, as a result, the discharge of water that does not meet the required standards.
In many countries the reuse of water is being encouraged. Many onsite systems produce water for surface irrigation of the required standard, but there are few domestic systems available that reliably produce water of a standard that can be recycled back to the home for non-potable use or have low enough nutrient levels to be disposed of on relatively small blocks of land.
WO02/089957 describes a treatment system for the treatment of primary waste on site. However, this treatment system alone does not produce water of high enough quality to be recycled back into the home for domestic use.
It would be desirable to provide a domestic waste treatment system, which produces water of high enough quality to be recycled back into the home for domestic use (e.g. non-potable use). It would be further desirable to provide a domestic waste treatment system, which is self-contained and which does not require regular human intervention to operate efficiently on a long-term basis.
It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative.